RPE calculator
Estimated max = weight × (1 + (reps + reps in reserve) ÷ 30). Example: 100 kg for 5 at RPE 8 gives about 123.3 kg.
RPE chart: % of your max
| Reps | @10 | @9.5 | @9 | @8.5 | @8 | @7.5 | @7 | @6.5 | @6 |
|---|---|---|---|---|---|---|---|---|---|
| 1 | 100% | 95% | 94% | 92% | 91% | 90% | 88% | 87% | 86% |
| 2 | 94% | 92% | 91% | 90% | 88% | 87% | 86% | 85% | 83% |
| 3 | 91% | 90% | 88% | 87% | 86% | 85% | 83% | 82% | 81% |
| 4 | 88% | 87% | 86% | 85% | 83% | 82% | 81% | 80% | 79% |
| 5 | 86% | 85% | 83% | 82% | 81% | 80% | 79% | 78% | 77% |
| 6 | 83% | 82% | 81% | 80% | 79% | 78% | 77% | 76% | 75% |
| 7 | 81% | 80% | 79% | 78% | 77% | 76% | 75% | 74% | 73% |
| 8 | 79% | 78% | 77% | 76% | 75% | 74% | 73% | 72% | 71% |
| 9 | 77% | 76% | 75% | 74% | 73% | 72% | 71% | 71% | 70% |
| 10 | 75% | 74% | 73% | 72% | 71% | 71% | 70% | 69% | 68% |
Our own chart: reps plus reps in reserve, run through Epley’s formula, with a single at RPE 10 set to 100%. Other published charts (built from lifters’ data) differ by a few percent.
How it is worked out
RPE (rate of perceived exertion) on the 10-point scale means 10 = nothing left, 9 = one more rep possible, 8 = two more. So reps in reserve (RIR) = 10 − RPE. A set of 100 kg for 5 at RPE 8 is treated as 7 reps to failure, and Epley gives 100 × (1 + 7/30) = 123.3 kg.
Questions
What is the difference between RPE and RIR?
They describe the same thing from two ends: RPE 8 means about 2 reps in reserve (RIR 2).
How accurate is it?
It is an estimate. Effort ratings are judgement calls, and above about 10 reps the formulas drift apart.
Is anything I type sent to you?
No. The calculator runs in your browser and nothing you enter leaves your device.